478 



DR MATTHEWS DUNCAN ON THE VARIATIONS OF THE FERTILITY 



made of it, the advantage over this table of including all mothers bearing children, 

 whether legitimate or not, alive or dead, in the Dublin Hospital. But in every 

 other respect, this second table presents what I judge to be more reliable data. 

 The former table contains a class of cases selected according to complicated con- 

 ditions which it is impossible to state, but which are the result of the correlated 

 circumstances of the Hospital, and of the class from which in Dublin it draws its 

 patients. In the second table the conditions of selection are fewer and less 

 important, the chief being the legitimacy, life and maturity, or at least viability, 

 of the offspring. Now the limits of the influence of these different conditions are 

 pretty well known, and the proportional differences between the two tables are too 

 great to be accounted for by these differences. The second table is thus shown 

 to be the more trustworthy. 



TABLE III.— Showing the Age of each of 16,301 Wives whose Children were 

 Registered in Edinburgh and Glasgow in 1855. 



Ages, . 



16 



17 



18 



19 



20 



21 



22 



23 



24 



25 



26 



27 



28 



29 



30 



31 



32 



33 



34 



Mothers, 



4 



28 



116 



228 



405 



543 



828 



888 



1024 



1058 



1063 



925 



1116 



875 



121 



545 



825 



645 



621 







Ages, . 



35 



36 



37 



38 



39 



40 



41 



42 



43 



44 



45 



46 



47 



48 



49 



50 



51 



52 57 



Total 



Mothers, 



691 



594 



409 



426 



287 



404 



142 



148 



80 



66 



50 



27 



6 



9 



4 



- 



2 



4 



1 



16,301 



1 



TABLE IV. — Showing the Ages of 16,301 Wives-Mothers in Edinburgh and Glasgow 

 in 1855, arranged in Periods of Five Years. 



Ages, . . . 



15-19 



20-24 



25-29 30-34 



35-39 



40-44 



45-49 



50-54 



55-59 



Total 



1 



Mothers, . . 



376 



3688 



5037 



3850 



2407 



840 



96 



6 



1 



16,301 



Percentage, . 



2-30 



22-62 



30-89 23-61 



14-76 



515 



-58 



•03 



— 





An inspection of this table shows again that the year of maternal life yielding 

 most recruits to the general population is the thirtieth, and an easy calculation 

 makes out that about three-fifths of the legitimately born population are derived 

 from women of 30 years and under, while two-fifths are derived from women 

 of 30 years and upwards. For, dividing mothers of 30 years of age, and 

 adding together those on each side of the point of division, we have on the side of 

 the younger 9708 mothers, and on the side of the elder 6593, giving a majority of 

 31 15 in favour of the younger. The mean age of the wives-mothers in this table 

 is above 29. 



From these data I conclude, 



